Apparatus for crimping textile yarns by false-twisting



July 7, 1970 J. RASCHLE 3,

APPARATUS FOR CRIMPING TEXTILE YARNS BY FALSE-TWISTING Filed April 18, 1969 INVENTOR. N Fascia 6 United States Patent 8 Int. Cl. D02g 1/04; D01h 7/92; F16h 13/12 U.S. Cl. 57-77-45 4 Claims ABSTRACT OF THE DISCLOSURE Apparatus for crimping textile yarns by the false-twist method utilizing axially parallel rollers including flat discs engaging a twist tube, and magnet means comprising elements arranged on each side of the discs to hold the twist tube in contact with the discs.

This invention relates to apparatus for crimping textile yarns, and more particularly to such apparatus for crimping by the false-twist method.

Apparatus for the crimping of textile yarns by falsetwisting is known wherein a twist tube is situated in the throat or crotch formed by two axially parallel rollers, the tube being in tangential contact with the rollers. One of the rollers is driven and the other runs idly as a guide roller, and the twist tube is urged against the rollers by means of magnets so as to be rotated at high speed. The yarn to be false-twisted is advanced longitudinally through the twist tube and is looped once around a cross-pin therein. In a particular execution of this known apparatus, each of the two rollers consists of two parallel discs which are maintained at an equal axial distance from each other by means of spacers, and magnetic attraction is effected by means of a permanent bar magnet arranged in the middle between the two discs and the two spacers. In another execution, the magnetic attraction is effected by means of a horseshoe magnet the horseshoe plane of which runs in vertical direction and the ends of the legs of which bear horizontal pole shoes which extend into the space between the discs and the spacers. Such apparatus is described in Patent No. 3,267,657.

With apparatus of this kind, very high speeds of revolution of the twist tube may be obtained, but the twist tube must present a minimum length so that it can exend across the parallel discs of the two rollers, the discs having to be maintained at a certain distance by the spacers which makes possible the arrangement of the permanent magnets between the discs. If, on the other hand, it is wished to increase the revolution speed of the twist tube while maintaining the same revolution speed of the driving roller, this is only possible by reduction of the dimensions of the twist tube.

The present invention is directed to creation of a falsetwisting device of the described kind which permits an increase of the speed of revolution of the twist tube by effecting a reduction of its dimensions. According to the invention, this problem is resolved by using rollers in the form of flat discs as well as magnet means, preferably in the form of two permanent horseshoe magnets the U-planes of which are parallel to each other and arranged such that two magnetic legs running in parallel with the disc surfaces are situated opposite the upper and lower disc surfaces. The ends of the legs are situated adjacent the respective ends of the twist tube. One such magnet can be situated opposite the upper and the other opposite the lower disc surfaces, or one leg of each of the "ice two horseshoe magnets can be situated opposite the upper disc surfaces and the other leg opposite the lower disc surfaces.

The apparatus of the invention presents the advantage that the rollers may be given the shape of flat discs of a thickness of between approximately 5 and 10 millimeters, whereby twist tubes with correspondingly small dimensions may be used. Furthermore, the twist tubes are not attracted magnetically by their central portion as in previous known false-twist devices, but by their two extremities, whereby the twist tubes are safely maintained in their position even at very high speeds of revolution.

Further specific features and advantages of the invention will be hereinafter more fully set forth with reference to the annexed drawings, showing a presently preferred emobdiment of the invention and certain modifications thereof, in which:

FIG. 1 is a perspective view illustrating one form of the invention; and

FIG. 2 is a perspective view illustrating another form of the invention.

Referring now to the drawings, and more particularly to FIG. 1 thereof, there is shown a roller 2 mounted for rotation on the shaft 15, and a moving belt 16 which runs in contact with the shaft to rotate same about the axis 1. An idling guide roller 4 is rotatable on the axis 3 and is positioned adjacent the roller 2 so that its sides or circular surfaces are in substantially the same planes as the corresponding surfaces of the roller 2. The rollers 2 and 4 may, for example, consist of a plastic material such as Vulcollan. In the throat or crotch formed between the two rollers 2 and 4, a hollow twist tube 5 is positioned, and this twist tube may consist of a suitable hard metal, and may be formed with enlarged terminal parts 6 and 7 consisting of a magnetic material.

As shown in FIG. 1, the parts 6 and 7 are under the influence of the permanent horseshoe magnets 9 and 10 the U-planes of which are horizontal. The lines 11 and 12 indicate the magnetic flux paths of the magnets 9 and 10, respectively.

A hollow cylindrical head 8 of non-magnetic material is fixed on the upper terminal part 6 of the twist tube 5; and a cross-pin (not shown) extends diametrically across the head 8 around which pin the longitudinally advancing textile thread (not shown) is wound once. The legs of magnet 9 are situated adjacent the upper surfaces 2, 4 of the rollers 2 and 4, and the legs of magnet 10 are situated adjacent the lower, non-visible surfaces 2", 4 of these rollers. The two magnets 9 and 10 must be of equal strength so that the terminal parts 6 and 7 of the twist tube 5 are equally attracted towards the rollers 2 and 4.

In the example illustrated in FIG. 2, the represented apparatus presents the same rollers 2 and 4 with the twist tube 5 arranged in the throat between the same. However, the U-planes of the two permanent horseshoe magnets 13, 14 are vertical, their legs 13 and 14 being situated opposite the upper roller surfaces 2' and 4' and the legs 13" and 14" opposite the non-visible lower roller surfaces 2" and 4". In this execution of the invention, no separate magnetic fluxes exist in the two magnets, but only one magnetic flux passes through both magnets, as indicated by line 15. This solution presents the further advantage that the magnets need not necessarily be of exactly equal strength.

From the foregoing description, it will be seen that 'I contribute by the present invention a false-twist apparatus for the crimping of textile yarns which apparatus utilizes rollers of only a single disc each and consequently twist tubes of smaller dimensions than were possible in such devices heretofore known. Those skilled in the art will appreciate that shorter twist tubes may be made of smaller diameter since the lateral stresses will be reduced and since in the present case they are supported centrally; and the smaller the diameter the greater the speed of revolution for a given annular speed of the discs.

What is claimed is:

1. Apparatus for crimping textile yarns by false-twisting by means of axially parallel rollers and a twist tube held in tangential contact therewith by magnet means characterized in that the rollers are in the form of fiat discs and that the magnet means comprise parallel elements arranged adjacent the opposite faces of the respective discs and with their ends adjacent corresponding ends of the twist tube.

2. Apparatus according to claim 1, wherein the magnet means are two permanent horseshoe magnets the planes of which are parallel with each other and so arranged that two legs of the magnet means are adjacent to the respective disc faces.

3. Apparatus according to claim 2, wherein one horse- 20 shoe magnet is adjacent one pair of corresponding disc faces and the other horseshoe magnet is adjacent the other pair of corresponding disc faces.

4 4. Apparatus according to claim 2, wherein one leg of each horseshoe magnet is adjacent one pair of corresponding faces of the discs and the other leg of each horseshoe magnet adjacent the other pair of corresponding faces of the discs.

References Cited UNITED STATES PATENTS 3,142,953 8/1964 Gassner et al. 5777.45 3,267,657 8/1966 Kunzle et a1. 5777.45 3,355,870 12/1967 Mattingly 5777.45 3,355,871 12/1967 Mattingly 5777.45 3,403,566 10/1968 Mattingly 5777.45 XR FOREIGN PATENTS 1,362,081 4/1964 France.

908,113 10/1962 Great Britain.

DONALD E. WATKINS, Primary Examiner US. 'Cl. X.R. 

